Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Potential Difference in spherical shell

  1. Feb 15, 2008 #1
    1. The problem statement, all variables and given/known data

    Figure 16.69
    A thin spherical shell made of plastic carries a uniformly distributed negative charge -7e-10 coulombs (indicated as -Q1 in the diagram). Two large thin disks made of glass carry uniformly distributed positive and negative charges 1.7e-05 coulombs and -1.7e-05 coulombs (indicated as +Q2 and -Q2 in Figure 16.69). The radius R1 of the plastic spherical shell is 7 mm, and the radius R2 of the glass disks is 4 meters. The distance d from the center of the spherical shell to the positive disk is 19 mm.

    (a) Find the potential difference V1 - V2. Point 1 is at the center of the plastic sphere, and point 2 is just outside the sphere.
    (b) Find the potential difference V2 - V3. Point 2 is just below the sphere, and point 3 is right beside the positive glass disk.

    Remember that the sign of the potential difference is important.

    2. Relevant equations
    E = (Q/A)/E_o

    3. The attempt at a solution
    I tried calculating the field from the capacitor and multiplying it, but I really think I'm going in circles. Anyone help?

    I'm so confused on how to begin... Please help.

    Attached Files:

  2. jcsd
  3. Sep 24, 2009 #2
    I also really need help with this problem. Any help?
  4. Sep 28, 2009 #3
    I also have question on this too can someone help us??
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook